Apparatus for optically detecting an extraneous matter on a translucent shield

Abstract

An apparatus for optically detecting the attachment state of extraneous matters to a translucent shield member. The optically detecting apparatus comprises a light-emitting unit having a plurality of light-emitting elements each emitting a light ray toward the translucent shield member, a photoelectric transducer unit having a plurality of transducer elements each receiving each of the light rays reflected on the translucent shield member, and a data processing unit coupled to the transducer unit. The transducer unit generates detection signals corresponding to the quantities of the received light rays and the data processing unit successively compares the level of each of the detection signals with a predetermined level to produce binary signals in accordance with the results of the comparison so that a binary signal pattern is defined at the respective transducer elements. The data processing unit determines the attachment state of the extraneous matters to the translucent shield member by comparing the defined binary signal pattern with a reference pattern.

What is claimed is: 
     
       1. An apparatus for optically detecting the presence of extraneous matter on a windshield comprising: first light-emitting means for emitting light from an inner side of said windshield toward an outer surface of said windshield to cause a light reflection form said outer surface;   second light-emitting means for emitting light from the inner side of said windshield toward an inner surface of said windshield to cause a light reflection from said inner surface;   first transducer means for receiving said light reflection from said outer surface of said windshield and generating a first detection signal corresponding to a quantity of the reflection light received by said first transducer means;   second transducer means for receiving a quantity of external light from an outer side of said windshield and generating a second detection signal corresponding to a quantity of external light;   third transducer means for receiving said light reflection from said inner surface of said windshield and generating a third detection signal corresponding to a quantity of the reflection light received by said third transducer means; and   data processing means responsive to said first, second and third detection signals for:   (a) successively comparing the level of said first detection signal with a first predetermined reference level so as to generate a first high-level signal when the level of said first detection signal is higher than said first predetermined reference level, and determining the presence of extraneous matters on said windshield on the basis of the number of the generated first high-level signals,   (b) comparing the level of said second detection signal with a second predetermined reference level so as to determine a second result and determining the degree of brightness outside said windshield in accordance with said second result, and   (c) successively comparing the level of said third detection signal with a third predetermined reference level so as to generate a third high-level signal when the level of said third detection signal is higher than said third predetermined reference level and determining the presence of extraneous matter on the inner surface of said windshield on the basis of the number of the generated third high-level signals.   
     
     
       2. Apparatus as in claim 1, wherein said first predetermined reference level is adjusted in response to said second result. 
     
     
       3. Apparatus as in claim 1, wherein said third predetermined reference level is adjusted in response to said second result. 
     
     
       4. Apparatus as in claim 1, wherein said first and second light-emitting means are located away from said inner surface of said windshield. 
     
     
       5. An apparatus for optically detecting the presence of extraneous matter on a windshield, comprising: first light-emitting means, located at an inner side of said windshield away from an inner surface of said windshield, for emitting light toward an outer surface of said windshield to cause a light reflection from said outer surface;   second light-emitting means, located at said inner side of said windshield away from said inner surface of said windshield, for emitting light toward said inner surface of said windshield to cause a light reflection from said inner surface;   transducer means for receiving both said light reflections from said outer and inner surfaces of said windshield and generating first and second detection signals respectively corresponding to respective quantities of the said light reflections from said outer and inner surfaces of said windshield; and   data processing means responsive to said first and second detection signals for:   (a) successively comparing the level of said first detection signal with a first predetermined reference level so as to generate a first high-level signal whenever the level of said first detection signal is higher than said first predetermined reference level and determining the presence of extraneous matter on the outer surface of said windshield on the basis of the number of the generated first signals, and   (b) successively comparing the level of said second detection signal with a second predetermined reference level so as to generate a second high-level signal whenever the level of each of said at least one second detection signal is higher than said second predetermined reference level and determining the presence of the extraneous matter on the inner surface of said windshield on the basis of the number of the generated second high-level signals.   
     
     
       6. Apparatus as in claim 5, further comprising an optical system located between said windshield and said transducer means for guiding the reflection light from the outer and inner surfaces of said windshield to said transducer means. 
     
     
       7. Apparatus as in claim 6, wherein said optical system includes filter means for transmitting only light having frequencies within a predetermined range. 
     
     
       8. Apparatus as in claim 6, wherein said first and second light-emitting means each comprise a respective plurality of infrared emitting diodes, said transducer means comprises an image sensor made of a silicon semiconductor, and said optical system comprises an infrared filter for transmitting only light with frequencies in a predetermined range. 
     
     
       9. Apparatus as in claim 6, wherein at least said first and second light-emitting means, said transducer means and said optical system are integrally encased in a housing disposed away from said inner surface of said windshield. 
     
     
       10. An apparatus as recited in claim 5, wherein said transducer means includes first transducing means for detecting the reflection light from the other surface of said windshield and second transducing means for detecting the reflection light from the inner surface of said windshield. 
     
     
       11. An apparatus for optically detecting the presence of extraneous matter on a windshield, comprising: a housing located at an inner side of said windshield away from an inner surface of said windshield;   first light-emitting means, located within said housing and having at least one infrared-emitting diode, for emitting at least one light ray toward an outer surface of said windshield, each of said at least one infrared-emitting element emitting one of said at least one light ray;   second light-emitting means, located within said housing and having at least one second infrared-emitting diode, for emitting at least one second light ray toward the inner surface of said windshield, each of said at least one second infrared-emitting diode emitting one of said at least one second light ray;   first transducer means, located within said housing, for receiving said at least one light ray reflected on the outer surface of said windshield and emitted from said first light-emitting means so as to generate at least one first detection signal corresponding to a quantity of the reflection light on the outer surface of said windshield;   second transducer means, located within said housing, for receiving said at least one second light ray reflected on the inner surface of said windshield and emitted from said second light emitting means so as to generate at least one second detection signal corresponding to a quantity of the reflection light on the inner surface thereof; and   data processing means, responsive to said at least one first detection signal and said at least one second detection signal from said first and second transducer means, for successively comparing the level of each of said at least one first detection signal with a first predetermined reference level so as to generate a first signal when the level of each of said at least one first detection signal is higher than said first predetermined reference level, and for successively comparing the level of each of said at least one second detection signal with a second predetermined reference level so as to generate a second signal when the level of each of said at least one second detection signal is higher than said second predetermined reference level, said data processing means determining the presence of the extraneous matter on the outer surface of said windshield on the basis of the number of the of the extraneous matter on the inner surface of said windshield on the basis of the number of the generated at least one second signal.   
     
     
       12. An apparatus as recited in claim 11, wherein said first and second transducer means comprise image sensor elements made of silicon semiconductor. 
     
     
       13. An apparatus for optically detecting the presence of extraneous matter on a windshield comprising: light emitting means, located at an inner side of said windshield, for emitting at least one first beam toward an outer surface of said windshield, and for emitting at least one second beam toward said inner surface of said windshield;   transducer means for receiving at least one of said at least one first beam after said at least one first beam has reflected from said outer surface of said windshield, and for receiving at least one of said at least one second beam after said at least one second beam has reflected from said inner surface of said windshield, said transducer means generating at least one corresponding first detection signal in response to each of said at least one reflected first beam, said transducer means generating at least one corresponding second detection signal in response to each of said at least one reflected second beam;   data processing means, responsive to said at least one first detection signal and said at least one second detection signal, for detecting the presence of extraneous matter on said outer surface of said windshield in response to said at least one first detection signal, and for determining extraneous matter on said inner surface of said windshield in response to said at least one second detection signal.   
     
     
       14. An apparatus as recited in claim 13, wherein said transducer means generates said at least one corresponding first detection signal in response to an intensity of each of said at least one reflected first beam; and said transducer means generates said at least one corresponding second detection signal in response to an intensity of each of said at least one reflected second beam. 
     
     
       15. An apparatus as recited in claim 14, wherein said data processing means detects the presence of the extraneous matter on said outer surface of said windshield in response to a first number of said at least one first detection signal that exceeds a first predetermined level; said data processing means determines said extraneous matter on said inner surface of said windshield in response to a second number of said at least one second detection signal that exceeds a second predetermined level. 
     
     
       16. An apparatus as recited in claim 15, further comprising an optical system located between said windshield and said transducer means for guiding the reflection light from the outer and inner surfaces of said windshield to said transducer means. 
     
     
       17. An apparatus as recited in claim 16, wherein at least said light emitting means, said transducer means and said optical system are integrally encased in a housing disposed away from said inner surface of said windshield. 
     
     
       18. An apparatus as recited in claim 17, wherein said optical system includes filter means for transmitting only light having frequencies within a predetermined range. 
     
     
       19. An apparatus as recited in claim 17, wherein said light emitting means comprises infrared emitting diodes, said transducer means comprises an image sensor made of a silicon semiconductor, and said optical system comprises an infrared filter for transmitting only light with frequencies in a predetermined range. 
     
     
       20. An apparatus as recited in claim 15, further comprising second transducer means for generating an ambient light signal in response to an intensity of external light introduced from an outer side of said windshield. 
     
     
       21. An apparatus as recited in claim 20, wherein said first predetermined level is adjusted in response to said ambient light signal. 
     
     
       22. An apparatus as recited in claim 20, wherein said second predetermined level is adjusted in response to said ambient light signal. 
     
     
       23. An apparatus for optically detecting the presence of extraneous matter on a windshield, comprising: first light-emitting means installed at the inside of said windshield and having a plurality of light-emitting elements each emitting a light ray toward the outer surface of said windshield;   second light-emitting means installed at the inside of said windshield and having a plurality of light-emitting elements each emitting a light ray toward the inner surface of said windshield;   first transducer means having a plurality of transducer elements respectively receiving the light rays emitted from said plurality of light-emitting elements of said first light-emitting means and reflected on the outer surface of said windshield, said first transducer means generating first detection signals corresponding to quantities of the reflection light received by said plurality of transducer elements;   second transducer means having at least one transducer element for receiving external light introduced from the outside of said windshield into said optically detecting apparatus, said second transducer means generating a second detection signal corresponding to the quantity of external light;   third transducer means having a plurality of transducer elements respectively receiving the light rays emitted from said plurality of light-emitting elements of said third light-emitting means and reflected on the inner surface of said windshield, said third transducer means generating third detection signals corresponding to quantities of the reflection light received by said plurality of transducer elements thereof; and   data processing means responsive to said first detection signals, said second detection signal and said third detection signals for successively comparing the level of said first detection signals with a first predetermined reference level so as to generate a first high-level signal when the level of each of said first detection signals is higher than said first predetermined reference level, for comparing the level of said second detection signal with a second predetermined reference level and for successively comparing the level of each of said third detection signals with a third predetermined reference level so as to produce a third high-level signal when the level of each of said third detection signals is higher than said third predetermined reference level, said data processing means determining the presence of extraneous matter on said windshield on the basis of the number of the generated first high-level signals, determining the degree of brightness outside said windshield in accordance with the result of the comparison of the level of said second detection signal with said second predetermined reference level and determining the fogging state on the inner surface of said windshield on the basis of the number of the produced third high-level signals.   
     
     
       24. An apparatus as claimed in claim 23, wherein said first predetermined reference level is adjusted in accordance with the result of the comparison of the level of said second detection signal with said second predetermined reference level. 
     
     
       25. An apparatus as claimed in claim 23, wherein said third predetermined reference level is adjusted in accordance with the result of the comparison of the level of said second detection signal with said second predetermined reference level. 
     
     
       26. An apparatus as claimed in claim 23, wherein said first and second light-emitting means are structurally integrated with each other, and said first to third transducer means are structurally integrated with each other. 
     
     
       27. An apparatus for optically detecting the presence of extraneous matter on a windshield, comprising: first light-emitting means installed at the inside of windshield to be in spaced relation to said windshield and having a plurality of light-emitting elements each emitting a light ray toward the outer surface of said windshield;   windshield to be in spaced relation to said windshield and having a plurality of light-emitting elements each emitting a light ray toward the inner surface of said windshield;   transducer means having a plurality of transducer elements which receive at least one of the light rays emitted from said plurality of light-emitting elements of said first light-emitting means and reflected on the outer surface of said windshield, and which receive at least one of the light rays emitted from said plurality of light-emitting elements of said second light emitting means and reflected on the inner surface of said windshield so as to generate first detection signals corresponding to quantities of the reflection light on the outer surface of said windshield and to generate second detection signals corresponding to quantities of the reflection light on the inner surface thereof; and   data processing means responsive to said first detection signals and said second detection signals from said transducer means for successively comparing the level of each of said first detection signals with a first predetermined reference level so as to produce a first signal when the level of each of said first detection signals is higher than said first predetermined reference level and for successively comparing the level of each of said second detection signals with a second predetermined reference level so as to produce a second signal when the level of each of said second detection signals is higher than said second predetermined reference level, said data processing means determining the presence of extraneous matter on the outer surface of said windshield on the basis of the number of the produced first signals and determining the presence of the extraneous matter on the inner surface of said windshield on the basis of the number of the produced second signals.   
     
     
       28. An apparatus as claimed in claim 27, further comprising an optical system provided between said windshield and said transducer means for guiding the reflection light from the outer and inner surfaces of said windshield to said transducer means. 
     
     
       29. An apparatus as claimed in claim 28, wherein said optical system includes filter means for transmitting only light with frequencies in a predetermined range. 
     
     
       30. An apparatus as claimed in claim 28, wherein each of said first and second light-emitting means comprises as said light-emitting elements plurality of infrared emitting diodes and said transducer means is made of an image sensor made of a silicon semiconductor and said optical system includes an infrared filter for transmitting only light with frequencies in a predetermined range. 
     
     
       31. An apparatus as claimed in claim 28, wherein said at least said first and second light-emitting means, said transducer means and said optical system are integrally encased in a housing which is placed to be spaced from said windshield. 
     
     
       32. An apparatus as claimed in claim 27, wherein said transducer means includes first transducing means for detecting the reflection light from the outer surface of said windshield and second transducing means for detecting the reflection light from the inner surface thereof. 
     
     
       33. An apparatus as claimed in claim 32, wherein said first and second transducing means are structurally integrated with each other. 
     
     
       34. An apparatus for optically detecting the presence of extraneous matter on a windshield, comprising: a housing placed at the inside of said windshield so as to be in spaced relation thereto;   first light-emitting means encased in said housing and having a plurality of infrared-emitting diodes each emitting a light ray toward the outer surface of said windshield;   second light-emitting means encased in said housing and having a plurality of infrared-emitting diodes each emitting a light ray toward the inner surface of said windshield;   first transducer means encased in said housing and comprising image sensor means made of a silicon semiconductor which receives the light rays emitted from said light-emitting means and reflected on the outer surface of said windshield so as to generate first detection signals corresponding to quantities of the reflection light on the outer surface of said windshield;   second transducer means encased in said housing and comprising image sensor means made of a silicon semiconductor which receives the light rays emitted from said second light emitting means and reflected on the inner surface of said windshield so as to generate second detection signals corresponding to quantities of the reflection light on the inner surface thereof; and   data processing means responsive to said first detection signals and said second detection signals from said first and second transducer means for successively comparing the level of each of said first detection signals with a first predetermined reference level so as to produce a first signal when the level of each of said first detection signals is higher than said first predetermined reference level and for successively comparing the level of each of said second detection signals with a second predetermined reference level so as to produce a second signal when the level of each of said second detection signals is higher than said second predetermined deference level, said data processing means determining the presence of the extraneous matter on the outer surface of said windshield on the basis of the number of the produced first signals and determining the presence of extraneous matter on the inner surface of said windshield on the basis of the number of the produced second signals.